Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: Check write tracking in all address spaces
kvm_gfn_is_write_tracked() checks only the supplied memslot, but page
tracking is per-address-space and shadow pages are shared across all
address spaces. With SMM, a GFN can therefore be write-tracked in one
address space and appear untracked through the other.
Check the supplied slot first, then the slot for the other address space.
This ensures all callers honor write tracking regardless of the active
address space. In particular, it prevents mmu_try_to_unsync_pages() from
marking an upper-level shadow page unsync and eventually triggering the
BUG in pte_list_remove().
[invert direction of the conditional. - Paolo]
CVSS Score
5.5
EPSS Score
0.001
Published
2026-09-29
Information disclosure in the Networking component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS Score
4.3
EPSS Score
0.002
Published
2026-09-29
Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 140.17, Thunderbird 153.4, Firefox ESR 115.42, and Firefox ESR 140.17.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-09-29
Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-09-29
Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-09-29
Privilege escalation in the Address Bar component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS Score
8.8
EPSS Score
0.002
Published
2026-09-29
Spoofing issue in the Downloads component in Firefox for Android. This vulnerability was fixed in Firefox 157.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-09-29
Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
CVSS Score
8.1
EPSS Score
0.002
Published
2026-09-29
Other issue in the DevTools component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.
CVSS Score
9.8
EPSS Score
0.004
Published
2026-09-29
Sandbox escape due to use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-09-29